概括：
我无法使用 Cisco IPSec 连接到 VPN，显然是因为输入共享密钥后它没有被保存（它始终保持空白）。
详细解释：
我使用 Cisco IPSec 创建了 VPN 连接并成功连接。突然（几个小时后）我断开了连接，并在尝试重新连接后收到以下错误：
“VPN 服务器未响应。请验证服务器地址并尝试重新连接。”
该地址没有问题，因此我检查了日志并发现：
Feb 22 17:59:35 gerry racoon[4401]: couldn't find the pskey by address 204.232.144.166.
我检查了共享密钥，发现它是空白的；我再次输入它，单击确定并立即打开它，再次得到一个空白的共享密钥。我再次输入共享密钥并尝试连接并得到以下日志：
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSetFillColorWithColor: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSetStrokeColorWithColor: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetCompositeOperation: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSetCompositeOperation: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextFillRects: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSetCompositeOperation: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextClipToRect: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetShouldSmoothFonts: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetFontSmoothingStyle: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetFontAntialiasingStyle: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSetFontSmoothingStyle: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetDefaultUserSpaceToDeviceSpaceTransform: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextConcatCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextDrawImages: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextRestoreGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 --- last message repeated 1 time ---
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetShouldSmoothFonts: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetFontSmoothingStyle: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSetFontSmoothingStyle: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 --- last message repeated 1 time ---
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetDefaultUserSpaceToDeviceSpaceTransform: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextConcatCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextDrawImages: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextRestoreGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 --- last message repeated 1 time ---
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 --- last message repeated 1 time ---
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetDefaultUserSpaceToDeviceSpaceTransform: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextConcatCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextSaveGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextDrawImages: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextRestoreGState: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
Feb 22 18:10:41 --- last message repeated 1 time ---
Feb 22 18:10:41 gerry com.apple.preference.network.remoteservice[4315]: CGContextGetCTM: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.
我搜索了有关此日志的信息，但无法确定它们是否与问题有关。
我尝试删除 VPN 连接并创建一个新的连接（顺便说一下，我不能使用相同的名称），但它也不起作用，所以我再次查看了日志：
Feb 22 18:16:26 gerry nesessionmanager[951]: Failed to load configuration with ID <__NSConcreteUUID 0x7fedfa504910> A7892601-20D6-4D80-88B7-8D2AA22CF4E1
Feb 22 18:16:26 gerry nesessionmanager[951]: Failed to create a session with type 1 and configuration ID <__NSConcreteUUID 0x7fedfa504910> A7892601-20D6-4D80-88B7-8D2AA22CF4E1
Feb 22 18:16:26 gerry nesessionmanager[951]: Failed to load configuration with ID <__NSConcreteUUID 0x7fedfa407490> A7892601-20D6-4D80-88B7-8D2AA22CF4E1
Feb 22 18:16:26 gerry nesessionmanager[951]: Failed to create a session with type 1 and configuration ID <__NSConcreteUUID 0x7fedfa407490> A7892601-20D6-4D80-88B7-8D2AA22CF4E1
不幸的是，没有这些日志我也无法做任何事情（相同的日志重复了大约 20 次并停止了），所以我再次删除了所有 VPN 连接，创建了一个新的（这次我可以选择相同的名称）并得到了不同的日志条目：
Feb 22 18:31:49 gerry nehelper[217]: 3C44D371-6954-4001-A2D7-0100446EDA8A.XAUTH: SecKeychainItemCreateFromContent failed: User interaction is not allowed.
Feb 22 18:31:49 gerry nehelper[217]: 3C44D371-6954-4001-A2D7-0100446EDA8A.SS: SecKeychainItemCreateFromContent failed: User interaction is not allowed.
最后，我搜索了我的 VPN 连接的钥匙串条目（在钥匙串访问中），但没有找到任何条目。我猜这可能是问题所在。
有什么想法可能是什么问题吗？我尝试在另一台 Mac（相同的操作系统，El Capitan）上连接，没有任何问题，但无法在我的 Mac 上使用 VPN。
谢谢你！
尝试连接后生成的完整日志（用于上下文）：
Feb 22 17:59:35 gerry nesessionmanager[951]: NESMLegacySession[VPN (Cisco IPSec):47CF9F0A-25FA-43A3-A675-9B30B55D84C0]: Received a start command from SystemUIServer[292]
Feb 22 17:59:35 gerry nesessionmanager[951]: NESMLegacySession[VPN (Cisco IPSec):47CF9F0A-25FA-43A3-A675-9B30B55D84C0]: status changed to connecting
Feb 22 17:59:35 gerry nesessionmanager[951]: IPSec connecting to server 204.232.144.166
Feb 22 17:59:35 gerry nesessionmanager[951]: IPSec Phase1 starting.
Feb 22 17:59:35 gerry racoon[4401]: accepted connection on vpn control socket.
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: IPSec connecting to server 204.232.144.166
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: Connecting.
Feb 22 17:59:35 gerry racoon[4401]: IPSec Phase 1 started (Initiated by me).
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: IKE Packet: transmit success. (Initiator, Aggressive-Mode message 1).
Feb 22 17:59:35 gerry racoon[4401]: >>>>> phase change status = Phase 1 started by us
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: none message must be encrypted, status 0x14a1, side 0
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry nesessionmanager[951]: IPSec Controller: IKE FAILED. phase 2, assert 0
Feb 22 17:59:35 gerry nesessionmanager[951]: IPSec Controller: retry IPSec aggressive mode with DH Group 2
Feb 22 17:59:35 gerry nesessionmanager[951]: IPSec Phase1 starting.
Feb 22 17:59:35 gerry racoon[4401]: IPSec connecting to server 204.232.144.166
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: Connecting.
Feb 22 17:59:35 gerry racoon[4401]: IPSec Phase 1 started (Initiated by me).
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: IKE Packet: transmit success. (Initiator, Aggressive-Mode message 1).
Feb 22 17:59:35 gerry racoon[4401]: >>>>> phase change status = Phase 1 started by us
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: port 62465 expected, but 0
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: try to get pskey by the peer's address.
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: couldn't find the pskey by address 204.232.144.166.
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: couldn't find the pskey for 204.232.144.166.
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: failed to generate SKEYID
Feb 22 17:59:35 --- last message repeated 1 time ---
Feb 22 17:59:35 gerry racoon[4401]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
Feb 22 17:59:38 gerry racoon[4401]: IKE Packet: transmit success. (Phase 1 Retransmit).
Feb 22 17:59:38 gerry racoon[4401]: port 37905 expected, but 0
Feb 22 17:59:38 --- last message repeated 1 time ---
Feb 22 17:59:38 gerry racoon[4401]: try to get pskey by the peer's address.
Feb 22 17:59:38 --- last message repeated 1 time ---
Feb 22 17:59:38 gerry racoon[4401]: couldn't find the pskey by address 204.232.144.166.
Feb 22 17:59:38 --- last message repeated 1 time ---
Feb 22 17:59:38 gerry racoon[4401]: couldn't find the pskey for 204.232.144.166.
Feb 22 17:59:38 --- last message repeated 1 time ---
Feb 22 17:59:38 gerry racoon[4401]: failed to generate SKEYID
Feb 22 17:59:38 --- last message repeated 1 time ---
Feb 22 17:59:38 gerry racoon[4401]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
Feb 22 17:59:41 gerry racoon[4401]: IKE Packet: transmit success. (Phase 1 Retransmit).
Feb 22 17:59:43 gerry racoon[4401]: port 37905 expected, but 0
Feb 22 17:59:43 --- last message repeated 1 time ---
Feb 22 17:59:43 gerry racoon[4401]: try to get pskey by the peer's address.
Feb 22 17:59:43 --- last message repeated 1 time ---
Feb 22 17:59:43 gerry racoon[4401]: couldn't find the pskey by address 204.232.144.166.
Feb 22 17:59:43 --- last message repeated 1 time ---
Feb 22 17:59:43 gerry racoon[4401]: couldn't find the pskey for 204.232.144.166.
Feb 22 17:59:43 --- last message repeated 1 time ---
Feb 22 17:59:43 gerry racoon[4401]: failed to generate SKEYID
Feb 22 17:59:43 --- last message repeated 1 time ---
Feb 22 17:59:43 gerry racoon[4401]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
Feb 22 17:59:45 gerry racoon[4401]: IKE Packet: transmit success. (Phase 1 Retransmit).
Feb 22 17:59:45 gerry nesessionmanager[951]: NESMLegacySession[VPN (Cisco IPSec):47CF9F0A-25FA-43A3-A675-9B30B55D84C0]: status changed to disconnecting
Feb 22 17:59:45 gerry nesessionmanager[951]: IPSec disconnecting from server 204.232.144.166
Feb 22 17:59:45 gerry racoon[4401]: IPSec disconnecting from server 204.232.144.166
Feb 22 17:59:45 --- last message repeated 3 times ---
Feb 22 17:59:45 gerry nesessionmanager[951]: NESMLegacySession[VPN (Cisco IPSec):47CF9F0A-25FA-43A3-A675-9B30B55D84C0]: status changed to disconnected, last stop reason None
Feb 22 17:59:45 gerry racoon[4401]: glob found no matches for path "/var/run/racoon/*.conf"
Feb 22 17:59:46 gerry racoon[4401]: Connecting.
Feb 22 17:59:46 --- last message repeated 1 time ---
Feb 22 17:59:46 gerry racoon[4401]: Unknown Informational exchange received.
答案1
问题确实出在 Apple 的钥匙串上，我无法解决它，所以我决定重置钥匙串（钥匙串访问 > 偏好设置 > 重置我的默认钥匙串），而且它成功了，唯一的（小）缺点是我需要再次添加所有密码。
我根本不知道是什么导致了这个问题，所以如果有人知道是什么导致钥匙串失效，请分享！
更新
问题又出现了，所以我猜是钥匙串和 vpn 之间出了问题。唯一能让它继续工作的方法就是一遍又一遍地重启钥匙串……有什么建议吗？
更新2
我终于找到了这个问题的根源：最新版本（5.1.2）Phusion 乘客修改/资源库/Preferences/com.apple.security.plist，导致钥匙串出现问题。
完整的问题描述和临时解决方案可以在这里找到这里。